Please consider reverting #4863

[stefanor]

Debian has been forced to revert c712663 in the distro's setuptools, for now. We upgraded to setuptools 78 just as we were beginning to freeze for the next release (Debian 13, trixie), and this change is particular has caused quite a bit of fallout.

One of the issues for us is that packages expect to be able to execute scripts from the build/scripts-* directories, but they now have an invalid shebang, so they have to be executed with an explicit interpreter. This can be to run tests, or get --help output to generate manpages for example.

Changing to explicitly specify a python interpreter is a change that can be made, but it'll take some time to coordinate. We have 5000 odd packages building with setuptools.

I understand that the build directory's contents can be considered to be an implementation detail of setuptools/distutils, that outsiders should not rely on. The problem here is just that it's been this way for so long that we've got used to it :(

In Debian's case we also have a wheel-centred Python package building approach that wouldn't run into this problem, but packages have to be converted over to it, and this will take time. There are many complex packages (Debian and upstream) that call setup.py directly, too.

[jaraco]

This is essentially a duplicate of #4934. I'm leaning toward saying that the best way forward here is to maintain a patch that provides the old behavior (as long as it's needed). Perhaps you can contribute to the conversation there by elaborating with a minimal reproducer that elicits the undesirable behavior (from Setuptools itself).